CERN-LHC. Measurements on the triboson W+-W+-W-+ production cross-section using two decay channels fully-leptonic W+-W+-W-+ -> l+-nu l+-nu l-+nu and semi-leptonic W+-W+-W-+ -> l+-nu l+-nu jj (with l=e,mu) in proton-proton collision data corresponding to an integrated luminosity of 20.3 fb-1 at a centre of-mass energy of 8 TeV with the ATLAS detector at the Large Hadron Collider. Limits are also sets on WWWW anomalous quartic gauge couplings.
The fully-leptonic channel (W+-W+-W-+ -> l+-nu l+-nu l-+nu ) is defined as (the exact definition is given in table 1 of the preprint):
- Exactly 3 leptons electrons or muons with pT(Lepton)>25 GeV and |eta(Leptons)|<=2.5
- If there are 2 Same Flavor Opposite Signe (SFOS) pairs, MET>55 GeV, if there is 1 SFOS, MET>45 GeV, and if there is 0 SFOS pairs no requirement is applied on the MET.
- If there is no SFOS pairs the invariant mass between any lepton paires mll > 20 GeV. No such requirements is applied in the presence of 1 or 2 SFOS pairs.
- The angle between the trilepton system and the pTMiss must be |phi_3l-phi_met|>2.5
- If there is no SFOS pairs, |mee-mZ|>15 GeV, if there is one SFOS pair mZ-mSFOS>35 Gev or mSFOS-mZ>20 GeV, and if there are two SFOS pairs mSFOS-mZ|>20 GeV.
- There should be at most 1 jet with pT>25 GeV and |eta|<4.5
- DeltaR(l,l)>0.1
The semi-leptonic channel (W+-W+-W-+ -> l+-nu l+-nu jj) is defined as (the exact definition is given in table 2 of the preprint):
- Exactly 2 same-charge leptons electrons or muons with pT(Lepton)>30 GeV and |eta(Leptons)|<=2.5
- Veto the presence of any third lepton with pT>6 GeV and |\eta|<2.5 GeV.
- In the ee final state mee<80 GeV or mee>100 GeV.
- The lepton pair should satisfy mll>40 GeV.
- There should be at least 2 jets with pT(j1)>30 GeV , pT(j2)>30 GeV and |eta|<2.5
- The dijet system should satisfy 65 GeV<mjj< 105 GeV and |Delta_Eta(jj)|<1.5
- If there is at least one electron in the events, MET>55 GeV.
- DeltaR(l,l)>0.1 and DeltaR(l,j)>0.3
